Modeling hyperpolarizabilities of some TICT molecules and their analogs

Abstract

Ground-state hyperpolarizabilities of a prototypical twisted intramolecular charge transfer (TICT) molecule (DMABN) and its analogues have been calculated by the finite-field SCF method at the CNDO/S level of approximation. The ground-state geometry of each molecule has been optimized by the MNDO metbod. Excited-state hyperpolarizabilities have been calculated by invoking the finite-field SCF single excitation CI method at the CNDO/S level of approximation. The study focuses attention on the possibly important role played by the TICT state in generating large quadratic polarizability in some of these molecules